1. Field
Embodiments disclosed herein relate to a motor to control so-called leakage magnetic flux.
2. Description of the Related Art
A motor is a machine that acquires rotational power from electric energy and generally includes a stator and a rotor. The rotor may be configured to electromagnetically interact with the stator and may be rotated by a force applied between a magnetic field and a coil current.
Permanent magnet motors may be classified, based on a constituent permanent magnet of a magnetic circuit and the shape of a rotor, into a surface mounted permanent magnet motor (SPM), interior permanent magnet motor (IPM), and spoke type permanent magnet motor.
Among these, a spoke type permanent magnet motor has a high magnetic flux concentration structure, and therefore may advantageously achieve generation of high-torque and high-output and a compact motor size with respect to the same output. The spoke type permanent magnet motor may be applied to a drive motor for a washing machine or a drive motor for an electric vehicle, which require high-torque and high-output.
Permanent magnet motors including the spoke type permanent magnet motor may be designed to realize high-speed motor driving using field-weakening control techniques.
In particular, electric field-weakening control to control a phase of current applied to a stator coil has been used. However, since such electric field-weakening control has restrictions on the maximum current which may be applied to a driving circuit, there exists an upper limit of current available upon so-called field-weakening control and a theoretically realizable maximum speed is limited.